Two Worlds Collide: Phineas and Ferb X Gravity Falls
by Ryan Choi
Summary: Phineas and Ferb, along with their friends, are dropped off at the Mystery Shack to stay for five days when their parents are too busy to be at home. Troubles arise when the Phineas and Ferb gang discover the supernatural of Gravity Falls, and some old enemies of the Pines twins return.
1. The News

**_The News_**

* * *

><p><strong>Flynn-Fletcher house: Backyard<strong>

Phineas and Ferb, along with their friends, are riding a flying merry-go-round.

"This ride is totally awesome." Isabella said, and the Fireside Girls nodded in agreement.

"Thanks, merry-go-rounds are fun, but what's even more fun than a merry-go-round is a flying merry-go-round." Phineas said.

Candace sees this and says, "Oh, they're so busted."

The merry-go-round comes back down to the ground, and the kids get off as Linda comes back home from grocery shopping.

"Mom!" Candace shouts as she rush off to get Linda to see the merry-go-round.

Just before she can see it, a ray beam hits the merry-go-round, causing it fly away by itself.

"But, but, but..." Candace says.

"Hey kids, who wants pie?" Linda asked.

"We do." all the kids replied.

Later that night, during dinner, a small conversation comes up. "Boys, and Candace, your father and I are gonna be too busy to be home for five days, but luckily, we found somewhere for you to stay during that time." Linda said.

"Where are we going?" Phineas asked.

"You'll be staying at the Mystery Shack in Gravity Falls, Oregon, there's rumor about supernaturals there." Lawrence replied.

"Eh, I see weird stuff everyday, what could possibly be more supernatural than what I've seen before?" Candace replied.

**Gravity Falls: Mystery Shack (Same time as Danville)**

Dipper and Mabel are hanging out in the living room, along with Soos, when Stan suddenly comes into the room.

"Alright, kids, Soos, I have an important announcement, more kids are gonna be staying at the Mystery Shack, so we have to be ready for them." Stan said.

"Ooh, are any boys coming? 'Cause Mabel's ready for them." Mabel said.

"Grunkle Stan, please tell me they're not gonna stay for the entire summer." Dipper said.

"Relax, kid, they're only staying for five days." Stan replied. "Surely you can handle that long."

**Danville: Bus stop (Next Morning, 8:00 a.m.)**

At the bus stop, a bus for Gravity Falls comes by, and Phineas, Ferb, and Candace, followed by Baljeet, Buford, and Irving (whose parents aren't that busy, but still tagging along), get on the bus.

In the bus, Stacy, Isabella (who's in her Fireside Girls uniform), and the Fireside Girls are there.

"Isabella, are your parents busy for five days, too?" Phineas asked.

"Nah, me and the girls are on a 5-day Fireside Girls field trip." Isabella said.

"Baljeet, Irving, and my parents aren't busy, we're just tagging along." Buford said to Isabella.

"And my mom wanted me to follow Ginger, 'cause she thought I might learn something." Stacy said.

"Alright, all of you, get settled, 'cause I'm about to drive, next stop: Gravity Falls, Oregon." The bus driver said, and the bus drives off in the distance.

* * *

><p><strong><em>Linda and Lawrence reveal that since they're busy, they're sending the boys and Candace to Gravity Falls for five days, and they're joined by their friends. Isabella and the Fireside Girls are on a field trip, Baljeet, Buford, and Irving decided to tag along, and Stacy was told to go with Ginger by her mom. What kind of supernaturals of Gravity Falls await them? To be continued...<em>**


	2. Mystery Shack Tour

**_Mystery Shack Tour_**

* * *

><p><strong>Gravity Falls: Mystery Shack<strong>

The bus comes by the Mystery Shack, and the kids, Candace, and Stacy get off at their stop.

Suddenly, they're greeted by Stan, who appears out of nowhere by using a smoke bomb trick. "Welcome to Gravity Falls's one and only, the Mystery Shack, and your home for the next five days." Stan said. "Come on in."

Stan shows the group around the Mystery Shack's gift shop. "Here we have a gift shop, everyone's welcome to spend their money for overcharged goods."

Stan leads the group into the museum. "Here we have the exhibits that are all supernatural to you, like this for example, the Ten Dragons of Gravity Falls." Stan says as he shows them a model showing 10 different-colored dragons near a monument. "Well-named due to each dragons representing 1 of the 10 different elements, there's Plant, Earth, Fire, Cold, Lightning, Water, Air, Metal, Light, and Dark."

"Uh, yeah, like I believe that." Candace said.

"Alright, the tour's over, get settled. The living room's behind this door, customers aren't allowed, but guests are." Stan says as he directs the group to a door in the gift shop.

The group enters the living room to find Dipper, Mabel, Wendy, and Soos watching Duck-tective on the TV.

**(Duck-tective)**

Duck-tective and the Constable are investigating a crime scene, when they find their culprit.

"Ah, you've found me, but you'll never catch me, suckers!" The culprit says as he throws a frying pan at the dectectives.

"Quack!" (Translation: "Duck!") Duck-tective quacks.

"What do you mean 'duck'? Aren't you a duck yourself?" The Constable asks, but then, gets hit by the frying pan.

"Oh, you meant that kind of duck." The Constable said.

"Quack Quack Quack!" (Translation: "Yes, yes I did.") Duck-tective replied as the culprit runs away.

"Will Duck-tective and his Constable capture the thief? Find out next time on... Duck-tective!" The announcer said.

**Mystery Shack: Living room**

"Hey look, dudes, they're here." Soos said, as he notice Phineas and Ferb's group.

"Hey, hey, welcome guests, "I'm Mabel, there's Soos, that's Wendy, and this is Dipper, we work at the Mystery Shack." Mabel introduced herself, Dipper, Soos, and Wendy.

"I'm Phineas, this is my brother, Ferb, my sister, Candace, our friends, Baljeet, Buford, and Irving." Phineas introduce himself, Ferb, Irving, Baljeet, Candace, and Buford.

"I'm Isabella, and these are my Fireside Girls troop, there's Adyson, Ginger, Katie, Holly, Milly, and Gretchen." Isabella introduce herself and the Fireside Girls.

"I'm Stacy, I'm Candace's best friend, and I'm also Ginger's older sister." Stacy introduce herself.

"Nice to meet you all, you wanna hang out with me, 'cause Mabel's the fun one." Mabel said.

* * *

><p><strong><em>Stan welcomes the guests to the Mystery Shack, and after they see some features of the Mystery Shack, they're introduced to Dipper, Mabel, Soos, and Wendy. What kind of events await them? To be continued...<em>**


	3. Evil Alliances

_**Evil Alliances**_

* * *

><p><strong>Gravity Falls: The jail<strong>

In Gideon's cell, Gideon is giving an evil eye at a picture of the Pines family.

"Just you wait, Pines family, I will get my revenge, especially on you Stanford, for exposing my "wittle" ol' secret, and you, Dipper, for keeping Journal 3 from me." Gideon mumbles on his bed.

Then, suddenly, Bill Cipher's presence fills the room.

"Hey, hey! What's up, Jailboy?" Bill says as he fully appears.

"What are you doing here? I told you, the deal's off, you failed to get me the combination to Stan's safe, so I had to improvise with dynamite, if you want your end of that former deal, then you're wastin' your time." Gideon said.

"Eh, forget about that. I just came to bust ya out of prison, in exchange for working with me on something." Bill said.

"I'm listenin'." Gideon replies as Bill mentions getting him out of prison.

"First, let's get out of here, then we can talk." Bill says as he makes a hole in the wall, and the two break out of jail.

**Gravity Falls: The forest**

Bill and Gideon are now at the foggy part of the forest, which is also where Gideon summoned Bill for the first time.

"Okay, Bill, what do you have in mind?" Gideon asked.

"As far as I know, Dipper has Journal 3, while Stan took your Journal 2, I'll just sneak into the Mystery Shack and find something useful in our plans, while you can try to remember where you found your psychic amulet so you can be psychic again." Bill said.

"Got it." Gideon says as he's about to go search for a new amulet, but he's stopped by Bill.

"Now hold on, if you're gonna go out into the forest, you need to dress properly." Bill says as he switch Gideon's prisoner uniform into his usual clothes.

"Yeah, that's much better." Gideon says and continues his way.

"Yeah, you be on your way, while there is someone's mind that I need to pay a little visit to." Bill said as he flies off to somewhere.

* * *

><p><strong><em>Bill Cipher return and he break Gideon out of prison to get revenge in the Pines. To increase their strength, Gideon is told by Bill to find a new psychic amulet to replace the one that was destroyed by Mabel, while he attempts to take care of something. What is Bill up to? To be continued...<em>**


	4. Dreamscaperers and Dragons

**_Dreamscaperers and Dragons_**

* * *

><p><strong>Mystery Shack: The living room<strong>

Phineas and Ferb's group, along with Dipper, Mabel, Soos, and Wendy are watching TV, while Stan is sleeping, when Bill suddenly appear out of nowhere, surprising all of them.

"Aah! Bill Cipher! What do you want?" Dipper demanded.

"Oh, not much, just some information that I can use to get back at you guys." Bill said.

"But I'll be honest with ya, I have no idea who they are, so they're good." Bill said, referring to Phineas and Ferb's group.

"You know there's no way we'd ever give up something important to you." Dipper said.

"Yeah, I figured that, so that's why, I'll just force myself!" Bill says as he enter Stan's mind.

Stan struggle in pain as Bill fully enters his mind.

"We have to get Bill out of there." Dipper said.

"But how are you gonna get into Stan's mind?" Adyson asked.

"It's all written on this journal, although some of the text can only be seen with black light, and plus, we've done this before." Dipper replies as he turns to Bill Cipher's page on Journal 3.

Everyone gets some candles set, and Dipper, Mabel, Soos, and Wendy put their hands on Stan's head.

"Just wait for us in the gift shop, we'll be back soon." Dipper says before chanting the incantation, "Videntus omnium. Magister mentium. Magnesium ad hominem. Magnum opus. Habeas corpus. Inceptus Nolanus!" And the eyes of everyone touching Stan's head go blue, the candle goes out, and after a blue explosion, they enter Stan's mind.

Phineas picks up Journal 3, which was left behind, and looks through it. "Whoa, this journal contains information about all sorts of supernaturals." He says as he reads the Gnomes page.

**Mystery Shack (Stan's mind)**

Dipper, Mabel, Wendy, and Soos arrive in Stan's mind.

"Alright, guys, we've gotta find Bill, and get him out of Grunkle Stan's mind before he..." Dipper says, but gets cut off when Bill reveals himself.

"Before I what? Find out something that could possibly bring harm to you?" Bill asked, as he enters the mind Mystery Shack.

"Come on, let's go get that isosceles maniac!" Mabel shouted, and they all run after Bill.

**Mystery Shack (Real world)**

Phineas continue reading through the journal and comes to a page about the 10 Dragons.

"Check it out, the 10 Dragons are real." Phineas said, and reads the description about them. "The majestic flying creatures of Gravity Falls, these 10 dragons represented 10 elements of Earth. There is Plant Dragon, Earth Dragon, Fire Dragon, Cold Dragon, Lightning Dragon, Water Dragon, Air Dragon, Metal Dragon, Light Dragon, and Dark Dragon. Regardless of the element, they all choose the forests of Gravity Falls as their home. Many have believed that there may be a way to extract the dragon's elements and transfer it to a human or something else. These creatures have shown that theycan be benevolt, despite a person's first impression on dragons as a giant frightening, man-eating monster. Instead, these dragons come out as giant, majestic, benevolent creatures."

"Wow, I'd like to see those dragons." Ginger said as Phineas finished the description.

* * *

><p><strong><em>Bill Cipher shows up at the Mystery Shack and enter Stan's mind for something. Dipper, Mabel, Soos, and Wendy follow Bill into Stan's mind to get him out. Meanwhile, the 10 Dragons are revealed to be real, and not fake as most of Stan's exhibits are. Can Dipper's group force Bill Cipher out of Stan's mind? To be continued...<em>**


	5. Mystery Shack Attack (Part 1)

**_Mystery Shack Attack (Part 1)_**

* * *

><p><strong>Mystery Shack (Real world)<strong>

Phineas and Ferb's group is hanging out in the Mystery Shack while they wait for Dipper's group to come back from Stan's mind.

"You know, reading about the supernaturals really encourage your sense of adventure." Katie says as she reads through Journal 3.

But then, she's surrounded by a blue light and lifted into the air, but Journal 3 is still on the ground, at the 10 Dragons page. "Whoa, what's happening?" Katie ask as she's left floating.

"How's that even possible? I'm psychic, but I'd never use psychic to do that!" Isabella shouts, but then, everyone is surrounded by the same blue light and gets lifted into the air.

"Who's doing this?" Holly asked.

"That would be me." Gideon, with a new psychic amulet, says as he enters the Mystery Shack.

"Who are you and why are you doing this?" Baljeet asked.

"The name's Gideon Gleeful, or Li'l Gideon, as I was called, but when the Pines came around, they ruined me! I was sent to prison, but luckily, Bill Cipher broke me out, and now I'm here for revenge, and also Journal 3." Gideon said.

He picks up and stares at the 10 Dragons page and says, "Hehehe, this is perfect, these dragons are what I need for my revenge against the Pines family. And I can drain them of their elements to give them to someone else, like for example, me! Now to meet up with Bill and we'll hunt down all 10 of these dragons and make their elements mine."

Then, he uses psychic and throws Phineas and Ferb's group backwards, before leaving with Journal 3 in his hands, laughing along the way.

**Mystery Shack (Stan's mind)**

In Stan's mind, the group look for Bill. "Ugh, where is that triangle guy. Hey, come out, triangle!" Wendy shouted.

"Maybe we should split, I'll go with Mabel, and you two can form your own group." Soos said.

"Fine with me." Wendy says as she and Dipper head in a different direction.

Mabel and Soos continue their way, when Bill suddenly appears and says in a low voice, "Your worst nightmares are coming your way!"

Bill then turns red and creates a ring of fire around himself and the group, before lifting the circled area up into the air, creating a fight arena.

"One nightmare coming up, this one's for Question Mark." Bill says as he creates a British dog man that Soos is afraid of. "'Ello, 'ello, 'ello! Who's crike for a stick in the pudding?" The dog man says as he pokes Soos with his cane.

"Now for the Shooting Star!" Bill shoots a beam at Mabel, turning her ugly and green.

"Gah, why'd you take away..." Mabel's voice becomes slow and low. "My cuteness!?"

Meanwhile, with Dipper and Wendy, they hear the fight, and head to their location.

"Now, I'll finish you!" Bill says as he readies another eye laser, but then, Dipper and Wendy fly by, and Dipper shoots an eye beam at Bill, knocking him back.

Wendy thinks of an ax and throw it at Bill, smashing him, but Bill reassembles himself.

"Hey guys, remember, in the mind you can make thoughts into reality." Dipper said, as he vaporize the dog man with another eye beam.

Mabel returns herself back to her normal appearance, and equips Kittens for Fists, and launch Kitten heads at Bill, and Soos use his Stomach Beam Stare on Bill.

Bill gets ready to attack, when a phone rings, and he reveals a screen on himself. "Yyyellow?"

"This is Gideon, I got Journal 3, we're capturing the 10 Dragons and transferring their elemental powers to me." Gideon says on the screen.

"Okey Dokey!" Bill says to Gideon before hanging up, then he turns to Dipper's group, "Well, I gotta tell ya, you never suspected it as a diversion for Gideon to steal Journal 3. Oh well, 'til we meet again." he says before leaving, and the group is left in disbelief.

* * *

><p><strong><em>Gideon gains a new psychic amulet to replace the destroyed one by Mabel, using it to take Journal 3, which he finds the 10 Dragons, and resolve to take their elemental powers. Meanwhile, in Stan's mind, Bill Cipher reveals that he was only distraction for Gideon. Can the heroes stop them? To be continued...<em>**


	6. Mystery Shack Attack (Part 2)

**_Mystery Shack Attack (Part 2)_**

* * *

><p><strong>White void (Stan's mind)<strong>

The gang are left in a white void by Bill, but then they start fading away.

"Well, Stan's waking up. And when he does, we have to stop Bill and Gideon." Dipper said.

**Mystery Shack (Real world)**

Stan fully awakens and Dipper's group is brought back to the real world.

"Alright kids, what happened?" Stan ask as he wake up.

"What do you mean?" Dipper asked.

"How you somehow showed up in my dream." Stan replied.

"Well, there's this triangle guy named Bill Cipher, and we followed him to get him out." Dipper said.

But suddenly, Dipper realize something. "Oh no! My journal!" Dipper shouts as he race into the gift shop, only to find it messed up, with Phineas and Ferb's group laying around, scattered around the room.

"Whoa! Hey kid, what happened in here?" Stan asks Phineas.

"Gideon, he has a psychic amulet." Phineas replied.

"Wait, but we destroyed it before." Dipper said.

"Then I guess he got a new one." Phineas said.

"We need to follow that Gideon guy, he knows about the 10 Dragons, and he plans to take their powers for his own." Milly said.

"But, how do we stop him? We don't have my journal to look it up." Dipper said.

"Actually, we did some reading on the 10 Dragons." Gretchen said, and she explains about the 10 Dragons.

"Well, now that we know enough, we have to stop Gideon and Bill." Dipper said.

"Hold it kid, you're not going..." Stan said.

"But Mr. Pines, we have to stop those guys." Soos interrupted.

"Don't interrupt, Soos. Anyway, if you're going, I'm coming along." Stan finished.

**Gravity Falls: The forest**

The heroes are walking in the forest.

"Ugh, tell me again, why me and Stacy had to come along as well." Candace complained.

"Do you really wanna be at the Mystery Shack if Gideon decides to come back?" Gretchen replied.

"You know she's got a good point there." Stacy said.

Meanwhile, somewhere else in the forest, Bill and Gideon, who have captured the Dark Dragon, Lightning Dragon, Cold Dragon, and Air Dragon, spy on the heroes looking for them.

"Well, well, well, if it isn't them? Clearly they want to stop us, but we are gonna stop them instead." Gideon said.

"Sure, I'll capture the remaining dragons while you go and stop them." Bill said.

"Oh, I sure will." Gideon says as he heads in the direction that the heroes are coming from.

* * *

><p><strong><em>Stan wakes up, causing Dipper's group to be released from Stan's mind. Then they find Phineas and Ferb's group after Gideon's raid, the heroes vow to stop Gideon and Bill's plan. Meanwhile, the villains already captured the Dark, Lightning, Cold, and Air Dragons. Can our heroes stop them? To be continued...<em>**


	7. More Allies

_**More Allies**_

* * *

><p><strong>Gravity Falls: The forest<strong>

The heroes are walking through the forest, when they spot two figures in the distance, one figure is laying on the ground, while the other one is sitting beside it.

They approach them, and the figures are revealed to be Iris sitting beside Ryan, while he's laying on the ground, and the heroes can clearly see something's wrong with him.

"Hey Iris, what are you doing here, and what's wrong with Ryan?" Isabella asked.

"Well, we came to investigate the forest of Gravity Falls. And while we were looking around, this yellow, one-eyed, pyramid-shaped guy with a top hat appeared, and then he proceeded to drain Ryan's technokinesis, and that left Ryan drained of energy, but fortunately, he's starting to recover." Iris explained.

"I told you, I'm fine, that triangle is gonna pay." Ryan says as he gets up.

"You're talking about Bill Cipher." Dipper said.

Suddenly, the Light Dragon flies into the sky, but then, it gets captured by psychic force and gets dragged back into the forest.

The Water Dragon flies out of the forest, and into the sky, but it gets shot down by a red beam and fall back into the forest.

The Metal Dragon flees from the red beams, it gets hit, but its scales are too tough for the brams to damage it, but it gets grabbed by the psychic force and gets dragged back into the forest.

"Oh no, those dragons got captured!" Baljeet said.

"At this rate, who knows how many dragons are still left free." Ginger said.

"Come on, we have to stop Bill and Gideon before things get any worse." Dipper said.

"Wait, I'm coming too, Bill Cipher harmed my brother, and now he's gonna get what's coming to him." Iris said.

"Yeah, even if I'm not in my full strength, I don't plan on just lying down." Ryan says, as he gets up.

Meanwhile, back at the villains' hideout, the captured dragons are locked in a machine with energy cages.

Bill is talking to Gideon through a phone. "You know, it's a good thing we met that guy who can control machines, 'cause his powers are making this machine function even better than expected."

"How many dragons do we need now?" Gideon asked.

"Cool your jets kid, I just got finished, but I can assure you, I'll have the remaining three, Plant, Earth, and Fire Dragons, soon." Bill replied.

"Anyways, have you found our friends yet?" Bill asked.

"I'm still working on it, which proves that we made our hideout somewhere good, since they can't seem to find us." Gideon replied, but then he hears the heroes' voices.

"If that Gideon tries to get us with his psychic powers again, this time, I'll beat the stuffings out of him!" Isabella's voice said.

"Oh, we shall see, my friend, we shall see." Gideon whispered as he follow the voices.

* * *

><p><em><strong>The heroes are joined by Ryan and Iris, who encountered Bill earlier, when Bill drained Ryan of his powers and some of his energy. Meanwhile, the Light, Water, and Dark Dragons are captured by the villains. Meanwhile, Gideon finally find the heroes. To be continued...<strong>_


	8. Isabella vs Gideon

**_Isabella vs. Gideon_**

* * *

><p><strong>Gravity Falls: The forest<strong>

The heroes continue their paths, when Gideon suddenly arrive from the bushes.

"Well, hello my friends, miss me?" Gideon ask as he show himself.

"No, but where's my journal?" Dipper demanded.

"Oh, you mean this?" Gideon ask as he pulls out Journal 3.

"Give it back!" Dipper demanded as he tries to tackle Gideon, but he move out of the way and lift Dipper into the air with his psychic.

"Dipper, Dipper, Dipper." Gideon said, "You thought you got rid of my powers for good when you destroyed my first amulet, but fortunately, I got a new one, and now I'm powerful again."

But then, he gets knocked back by a wave of pink psychic energy, and drops Dipper.

"Hey, what was that?" Gideon ask as he get up.

He gets his answer when he looks at Isabella, whose hands are surrounded by her own psychic energy.

"You're not the only one who have psychic powers." Isabella said.

"So, wait, do all of you have powers or something?" Stan asked.

"We'll explain later, but now we have to stop the bad guys."Adyson said.

"You guys go on, I got some score to settle with this guy." Isabella said.

"Are you gonna be alright?" Holly asked.

"Trust me, I can handle this." Isabella said.

"You sure, 'cause I can be a help..." Buford said, but get cut off.

"Buford!" Isabella shouted.

"Alright, have it your way!" Buford said, and the heroes rush toward the direction that Gideon came from.

"Looks like it's just you and me, girly." Gideon said.

"The name's Isabella!" Isabella shout as she shoots a psychic wave at Gideon.

Gideon retaliates by picking up a boulder and throwing it at Isabella, but she dodge it by using psychic to levitate.

"Psychic Beam!" Isabella shoots a multi-colored beam at Gideon, which knocks him back.

Gideon holds Isabella in place with telekinesis, but Isabella use her own telekinesis to lift a small log and drop it on Gideon, breaking his concentration and causing him to release her.

"Psychic Punch!" Isabella punches a fist of psychic energy at Gideon, slamming him to a tree.

Isabella removes the amulet from his neck and says,"It's over, Gideon, I won."

Then, she throws the amulet to the ground.

"My amulet!" Gideon says as the amulet breaks.

"Fake psychic can't compare to actual psychic." Isabella said.

"Oh, you haven't seen the last of wittle ol' me." Gideon says as he walks backwards into the shades of some trees.

"Weird guy, and anyway, I better catch up with the others." Isabella says as Gideon walks out of sight.

* * *

><p><strong><em>The heroes run into Gideon, who tries to get in their way, but Isabella decides to fight him. In the end, Isabella defeat Gideon and destroy his amulet. To be continued...<em>**


	9. The Maze Trap (Part 1)

_**The Maze Trap (Part 1)**_

* * *

><p><strong>Gravity Falls: The forest<strong>

The heroes continue to look for Bill, when Isabella catch up with them.

"Isabella, you caught up fast, did you beat that Gideon kid?" Stacy asked.

"Yup, and plus, I smashed his amulet, so he doesn't have his powers anymore." Isabella replied.

"Whew, good, 'cause when Gideon had it before, it was a ton of trouble." Mabel said.

"Come on, Bill must be this way." Dipper said, and the heroes continue their way.

Meanwhile, back at the villains' hideout, Bill now have captured the Plant and Fire Dragons.

"So she beat Gideon, huh, oh well, but once we have all 10 dragons, we're guaranteed to win." Bill said.

"But they're comin' fast, you got a plan to stall them?" Gideon asked.

"Relax, I thought of that and set up a trap for them." Bill said.

Meanwhile, the heroes are still walking, when a trapdoor opens underneath them and the fall into a maze.

**Gravity Falls: The maze**

"What the...? Did Bill set this up?" Wendy asked.

"Yes! Welcome to my maze trap!" A picture of Bill Cipher said. "Let this be a warning, if you wish to leave this maze, then you must explore through it and reach the end."

"Maze?! Why did it have to be a maze?" Candace complained.

"Oh, don't worry, the other option is to wait until we capture the last dragon and take their powers, then the maze will automatically free you." The Bill picture said.

"We can't wait that long, we have to stop them from harming the dragons." Ginger said.

"Yeah, and plus, if Gideon wanted this to be unsolvable, then we should totally solve this maze and rub it in his face." Stan said.

"I should take lead, I'm a good problem solver." Dipper said, and they start exploring the maze.

They come to a locked door, with its switch up high, but Phineas shoot a rope to pull the switch. "Rope to the rescue!" Phineas said.

A wall of fire blocks their path, but Ginger puts it out by making rain fall on the fire. "Rain puts out fire." Ginger said.

They walk into a dark room, but Gretchen solve the problem by creating light. "This room need some light." Gretchen said.

An electric fence blocks their way, but Adyson, with her rubber body, walks through the fence harmlessly, and shuts down the fence, allowing everyone else to get through. "Electric won't work on my rubber body." Adyson said.

The heroes come to a gap, but Katie builds a bridge out of snow. "Snow can be compressed to the point where it's strong as steel." Katie said.

They come across a locked door, and its key has wings, so its flying around, but Milly catch it by turning into half-falcon, and use it on the door to open it. "I can fly by becoming half-falcon." Milly said, and the heroes continue to the next room.

* * *

><p><em><strong>After beating Gideon, Isabella catch up to the other heroes, meanwhile, Bill captured the Plant and Fire Dragons. As the heroes get close to the villains' hideout, they fall into a maze trap. Can they get out in time to stop Gideon? To be continued...<strong>_


	10. The Maze Trap (Part 2)

**_The Maze Trap (Part 2)_**

* * *

><p><strong>Gravity Falls: The maze<strong>

Dipper is playing chess with a black figure, he moves his white knight two spaces left and one space down, his rook, bishop, and knight checkmate the black king, and the door opens, allowing them to continue.

Mabel start a conversation with a gatekeeper, but she eventually start annoying him to the point where he lets them pass.

They come across a puzzle door, with a key nearby, Gretchen solves it to reveal a shape of a giant keyhole, then they insert the key into a smaller keyhole in the picture, opening the door, and allowing them to continue.

In a ball pit, Holly, Ginger, and Buford dive in to look for a key, Buford finds it and use it on the lock, which opens the door.

Soos enter a staring contest with a stone figure, and the figure loses, and it allows the heroes to pass.

The next puzzle is a math problem, but Baljeet use his smarts to figure out the answer.

Stan is dealing with a figure that's acting as a customer, Stan use his con to trick the figure, the figure surrenders and opens the next door.

The heroes come across the final puzzle, but it gets blocked by a wall, but Buford punch it and the door retreats, opening the exit, and allowing them to finally exit the maze.

**Gravity Falls: The villain's lair**

Everyone is out of the maze, and arrive at the villains' lair, where now they have captured the Earth Dragon, and completing the 10 Dragons.

"Oh, would you look at that, you solved my maze." Bill said as he turns to face the heroes.

"We're gonna stop you, you... you... Isosceles Menace!" Mabel said.

"Sorry, but that ain't happening!" Gideon says as he press a button.

The platform that the heroes are standing on, suddenly spring up, knocking the heroes down when they land.

"Now let's activate this machine and the dragons' powers will be ours." Bill said as the machine starts up, and prepare to fire a ray at the villains.

"I can't let them do this, I have to stop them!" Ryan says as he get up.

Ryan charges towards Gideon and Bill and tackles them out of the way, but in the process, ends up taking the shot himself.

Ryan struggles in pain as he continues to be zapped by the ray, then a smoke appears covering the screen, leaving everyone unable to see through the smoke.

The ray stops, but Ryan's silhouette through the smoke starts changing, and it slowly begins to take on the appearance of a dragon.

* * *

><p><strong><em>The heroes finally exit the maze, and confront the villains, but they get knocked down quickly. The villains activate the machine, but Ryan gets them out of the way, but takes the shot himself. What happened to him? To be continued...<em>**


	11. Dragon vs Pyramid Demon (Part 1)

**_Dragon vs. Pyramid Demon (Part 1)_**

* * *

><p><strong>Gravity Falls: The villains' lair<strong>

The smoke clears, and everyone gets up.

"Hey wait, what happened to Ryan? He took the shot when he prevented Bill Cipher and Gideon from gaining the dragons' power." Phineas said.

"Ryan! Where are you?" Iris called out.

Then, suddenly, a humanoid dragon that's about the height of Stan, in the appearance of a Fire Dragon, and wearing a silver chestplate with a turquoise gem in the center, and silver leggings, suddenly descend from the sky.

"I'm here." the dragon said.

"Ryan, is that you?" Iris asked.

"Yes, it's me, when I took the shot, it gave me not only a dragon's form, but I can also use their elements, I just have to switch forms, but I can't change back to normal, I would say that this is my new default appearance." Ryan said."And this does not bother you at all?" Baljeet asked.

"Not quite, I actually feel much better, I feel like all the energy that Bill drained from me suddenly came back." Ryan replied.

"And look, the dragons seem fine, too." Soos said, as he points to the locked-up dragons.

"I say it's time for them to go free." Isabella says as she release the dragons, and they all fly away.

"You know with those chestplate and leggings, you're like a Dragon Knight." Phineas said.

The heroes' moment is ruined when Gideon and Bill Cipher suddenly reveal themselves.

"You! You moved us out of the way, and you ended up taking the shot yourself!" Gideon said.

"Want me to get back at them?" Bill asked.

"Oh, please do." Gideon replied.

"You better watch out..." Bill said, "'Cause it's time for payback!" Bill continues in a deep voice, and he grows giant.

"Ah! He's big!" Mabel said.

"Now I'm coming to get ya!" Bill says as he start shooting eye lasers at the heroes.

Ryan flies off to somewhere, while the rest of the heroes make a run for it.

"Where's Ryan going?" Holly asked.

"He ran away, and so should you." Bill said, but then he gets shocked by a lighting blast.

"Hey, who did that?" Bill asks as he turn around, and he finds his answer.

"Pick on someone your own size." Ryan says, now in Lightning Dragon form, as he also grow to giant size.

"Whoa! Ryan can also grow giant!" Gretchen said.

"You know, maybe I will, and after I beat you, maybe Gideon and I'll use you to power the machine instead, it's practically a 10 in 1 offer, I should take it." Bill said.

"Why don't you try!" Ryan challenged.

"I accept your challenge! GRAAAH!" Bill says and he lets out a battle cry as he charge toward Ryan.

"Bring it, GRAAAH!" Ryan lets out a battle cry and charge toward Bill Cipher.

* * *

><p><strong><em>Ryan is revealed to have gained a dragon form due to the ray, and he also have an armor that allows him to change elements. The villains refuse to admit defeat just yet, and Bill grows giant to defeat the heroes, but Ryan reveals that he can also grow to giant size. Now, Ryan and Bill Cipher get ready to fight each other. To be continued...<em>**

* * *

><p><strong><em>AN: In Fire Dragon form, Ryan's main body color is red, with orange as secondary, he have yellow horns on his head. _****_As Lightning Dragon, his color scheme is mainly yellow, with cyan as secondary, his horns in this form are white._**


	12. Dragon vs Pyramid Demon (Part 2)

**_Dragon vs. Pyramid Demon (Part 2)_**

* * *

><p><strong>Gravity Falls: The forest<strong>

Bill Cipher, and Ryan, as a Lightning Dragon, both in giant size, are about to duke it out.

"Taste my eye beams!" Bill shouts as he shoots at Ryan, but he flies up to dodge.

"Thunder Charge!" Ryan surrounds himself with electricity and tackle Bill.

"Oh yeah? Take this, Point-Blank Eye Beam!" Bill says as he flies closer to Ryan while repeatingly shooting lasers.

"Ryan! Look out!" Irving gives Ryan a heads-up.

The gem on Ryan's chestplate glows, and he change from Lightning Dragon to Metal Dragon.

Bill's lasers hit Ryan, but the Metal Dragon's scales are too tough.

"Whoa, Bill's lasers can't break through the Metal Dragon." Phineas said.

"Ten Iron Claw Blades!" Ryan scratch Bill with the claws on each of his 5 right fingers, followed by the claws on his 5 left fingers.

"Ow! That was sharp!" Bill says in reaction to getting scratched, and Ryan change into Dark Dragon.

"Take this, and this, and this, and this!" Bill shoots laser balls from his hands.

"Darkness Drill!" Ryan spins into a drill, while avoiding the laser balls, and hit Bill head-on.

"Aagh!" Bill screams as he gets hit.

"Ray of Darkness!" Ryan fires a darkness beam from his mouth.

"Try this on for size!" Bill says as he create a barrier to block the attack.

"Hmph, not bad, but I can make that barrier disappear, Dark Maiden!" Ryan covers himself with his cape-like wings, and release a swarm of bats made of darkness, the bats break through Bill's barrier.

"Whoa." Ferb said.

"What?!" Bill says in response to his barrier being destroyed.

"Horn Drill!" Ryan change into Earth Dragon, spins his horn and headbutt Bill.

"I'll be back!" Bill shouts as body cracks into many black pieces and disappear, and Ryan returns to normal size.

"Yeah, go dragon!" Wendy cheered.

"Um, I guess I'll be going now." Gideon says as he tries to flee, but Ryan lift him by the collar with the tip of his horn. "Where do you think you're going?"

"Hey, let me go, grr!" Gideon says as he struggle to get free.

Everyone laugh at Gideon.

"I think it's about time we got Gideon back to prison." Dipper said.

"Yeah, don't worry, I'll call the cops to take him away." Candace said as she dials 911 on her phone.

Soon, Sheriff Blubs and Deputy Durland arrive to arrest Gideon.

"You kids done a good job of catching this fraud." Blubs said.

"You're going back to jail, ya little liar!" Durland says to Gideon as he handcuffs him.

And the police duo drives off with Gideon in the back seat.

* * *

><p><strong><em>Ryan and Bill Cipher continue their battle, and Ryan wins by switching forms, Lightning, Metal, Dark, and finally defeats Bill as Earth Dragon. And in the end, Gideon is taken back to jail. To be continued...<em>**

* * *

><p><strong><em>AN: As Metal Dragon, Ryan is mainly silver with gray, his horns are black. As Dark Dragon, he's mainly dark navy with indigo, his horns are magenta-colored, and his wings become cape-like. As Earth Dragon, he's mainly brown with orange, his horn is white and drill-like, it's positioned to enable a drill headbutt._**


	13. The End and Goodbye

_**The End and Goodbye**_

* * *

><p><strong>Gravity Falls: The forest<strong>

"Ah, Gravity Falls is much more relaxing when that pest, Gideon isn't around to ruin it for me." Stan said. "Now let's get back to the Shack and relax."

"No need to walk, I'll just fly to the Shack." Ryan says as he grow giant. "Get on."

Everyone does so, and he flies to the Mystery Shack.

**Gravity Falls: Mystery Shack**

Ryan arrives back at the Mystery Shack, and once everyone's back on solid ground, Ryan return to normal size.

"Wow, that was awesome." Phineas said.

"Uh, I'm not usually the first one to notice some things, but what's gonna happen with Ryan? He can't just go around places looking like a dragon." Stacy pointed out.

"Hey, Dipper, does that journal have anything about something that can create disguises?" Adyson asked.

"Well, hold on, I might need blacklight." Dipper says as he heads inside the Mystery Shack.

After a few minutes, he comes out and says, "Journal 3 doesn't have anything about a disguise maker, and I checked clearly."

"Well, kid, maybe there's still one way." Stan said. "This is private."

Stan goes into the Shack and few minutes later, he comes out with Journal 2.

"Wait is that...?" Dipper asks about Journal 2.

"Yes, it's Journal 2, I stole it from Gideon when I revealed that he's a fraud." Stan replied.

"Anyways, here's what I found..." Stan says as he turns to a page.

It reads the Face of Changeling, "This mask is known to generate a disguise on anyone who wears it. However, it can you can only choose one disguise, so choose carefully." The description reads.

After a screen wipe, they have the Face, Ryan tries it on, and his appearance change back to his human appearance, including his clothes before his morph into dragon.

"It's a good thing it also allows clothes." Phineas said.

"Well, no need to wear this here." Ryan says as he takes off the Face, and he reverts back into a dragon.

**Mystery Shack (5 days later)**

The time for Phineas and Ferb's group to go back to Danville arrives.

"Well, I guess the day for us to go home finally came around." Phineas said.

"Hey, Ryan, can we can ride on you?" Irving asked.

"Alright, gladly." Ryan says as he grows giant.

"You know what? At first I wasn't sure about you guys coming to stay with us, but now, I'm glad that you guys came." Dipper says as Phineas and Ferb's group holds onto Ryan.

Phineas and Ferb's group wave goodbye to the Mystery Shack group.

"Hang on tight, 'cause it's a long way back to Danville." Ryan says and he takes off, while Iris follows by spinning her hair like a helicopter to fly.

* * *

><p><strong><em>After finally dealing with the villains, the heroes return to the Mystery Shack. After Stacy points out Ryan's inability to change back to normal, the gang heads out one more time to find a mask that can create disguises. After five days, it's time for Phineas and Ferb's gang to go home, and they get a ride from Ryan. The End<em>**


End file.
